BOOSTER SHOTS: Oddities, musings and news from the health world

Bisexuals exist. Duh! Or duh?

Gay and bisexual men haven't always seen eye to eye on bisexuality… (REUTERS/John Vizcaino )

Earlier this summer, scientists at Northwestern University found that bisexual men exist.

Duh! Or would that be: Duh?

As the Los Angeles Times reported in this recent examination of "duh science," some research seems so painfully obvious it makes you wonder why scientists even bothered to go through with it. (In this case, even one of the Northwestern scientists admitted to the New York Times that the research might make people go "Well, duh!" at first glance.)

But a closer look often shows that even when conclusions seem self-evident, there can be good reasons to delve into duh. The bisexuality research, which was published in the journal Biological Psychology, might be such a case, because it challenges a widely held notion -- not to mention a controversial paper, also out of Northwestern -- that bisexual men, at least according to one definition, don't exist at all.

In the earlier Northwestern study, which was conducted in 2005, researchers recruited self-described bisexual men and measured their genital arousal as they were shown erotic movies showing only men, or erotic movies showing only women. The scientists, who also observed homosexual and heterosexual men as part of the study, discovered that most of the bisexual men were aroused by looking at only one sex or only the other (usually men).

This time around, the team (which included at least one scientist who had been involved in the previous paper) recruited their subjects differently, requiring that they had had sexual and romantic relationships with people of both sexes. This group of bisexual men were aroused by both men and women.

So why does that matter? Because, as the authors wrote, "there is a long history of skepticism about whether [men who have had sexual experiences with both men and women] also have substantial sexual attraction toward both sexes" -- that, as a New York Times report about the 2005 research reported, you're either "gay, straight or lying." Bisexual people, and many others, don't buy it.

Showing that at least some bisexual men have a measurable physical response to both women and men probably won't quiet the debate -- the authors noted that "it remains unclear which pattern is most typical of contemporary bisexual men: the present results supporting a bisexual arousal pattern, or previous results not finding one." But the work, obvious as it may seem, provides some non-obvious data to inform the conversation.